The 5.29 Mega Thread!!

I now have a whining noise at higher speeds and when decelerating which is louder at higher speeds.Idk what to even do but i'm desperate at this point bc I just don't want to mess anything up. It really all feels ok as far as shifting and driving but the whine just doesn't seem it should be there. East coast gear supply and a local well known mechanic that does a lot of gear work honestly on jeeps says that aftermarket gears will just be louder and that things should be fine as long as everything seems normal other than the whine and it doesn't get worse. At lower speeds like 50 or below its almost non existent. I also just had new suspension installed and I do think i need some adjustments to be perfect there,i had a light light whine even after the lift and before the gears and had some pretty heavy vibrations at first but putting a couple hundred pounds in the bed brought the rear down some and helped the vibrations out almost completely. About advice would be greatly appreciated, any one else dealing with this? Are these gears really just louder and do this? Should I be concerned? Is there anything I should or can do to help it? Thanks

 

I have a gear whine around 70. It’s pretty much non existent below that. Pretty common to have gear whine with aftermarket gears. Not sure why.

 

Does it seem more upon declaration at higher speeds?I just don't know what's an acceptable amount of noise/whine or not honestly, as I said I'm just trying to do everything without any issues and this far I've followed everything to a T as recommended. It seems to run great, shifts smoothly and pulls good on the inclines and roads I used to have trouble on with an empty bed and I've had about 250lbs extra in the bed all week!Does the whining i'm dealing with possibly get any better, i'm still only at about 744 miles since install

 

Two biggest reasons;
-Performance gears are cut for performance, not NVH
-Shorter gears have fewer teeth on the pinion gear
3.91=43/11 tooth count
5.29=37/7 tooth count

 

Me, my dad, and a buddy got my gears put in this weekend. So far ive babied it but can already tell a bit of a difference. Now to get them broke in.

 

Just an FYI for anyone looking to get 5.29's from Nitro in the near future, they are currently on back order for the next 3 to 4 months. I found out the hard way!

 

Sub

 

Pretty fuckin’ stoked for you @tweakit88 cant wait to catch up in TN for the ATR 2019

 

Man i cant wait either. Thats gunna be a damn good trip for sure.

 

Can someone elaborate on the governing issue? I was dead set on 5.29’s, but the governing issue has me worried.

 

I seriously don't think there is an issue. Currently no issues for me [5.29s+33s] -- I have yet to find the governor at all during my ownership of the truck. The gears should have basically nothing to do with the speedo as the Tacomas read off the ABS sensor unless I am mistaken.

 

Correct. The speed is measured off the ABS sensors.

 

Thanks for the reply, maybe it’s just a few rare circumstances. I am pretty much stock on 33” tires and sliders. Another thing i have heard is that the 4.88’s get better gas mileage over 5.29’s? Doesn’t make sense to me as lower gears would be better mileage?

 

Lower gears getting better mileage is a bit of a myth and I don't have any empirical data to support the claim. Moving from stock gears 3.90 to 5.29s on stock tires I lost an average of 1 mpg combined. I lost much more if I was driving exclusively stop-and-go or city driving.

The biggest hit to mpg is tire size. When I shifted to 35s my mpg ranges between 13-16mpgs. I never ran 35s on stock gearing so I can't account for whether or not mpg is improved with lower gearing on larger tires.

Most people are reporting a slight mpg increase with the lower gearing and larger tires but I have seen no real metrics to support it so it's a bit anecdotal

 

Now that you have the 35s how’s it driving overall?

 

Yep, I never really understood that either. The whole engine efficiency, torque and HP curves, transmissions, drive train efficiency, vehicle weight, geography/terrain, driving style makes the whole thing murky and unpredictable from one person to another. To say "____ tire size and ____ gearing with result in the better mpg." is silly. I throw that whole idea of "lower rpm gets better mileage" BS in with the other offroad internet myths like "beadlocks are illegal".

 

Thanks for the input guys! Sorry if it was a dumb question just trying to decide what route to go with.

 

BUT, what if the speed limiter is governed by rpm/gear, or some other calculated data, rather than just wheel speed alone? That would explain why the limiter varies between vehicles with different gear/tire diameter setups...
Disclaimer: I have no actual answer, just thinking out loud...

 

https://www.tacomaworld.com/threads/the-5-29-mega-thread.557305/page-20#post-19994755

 

What the cpu does with the data, I can’t say because I don’t know.